“Parasites of the mind”*: traumatic memories and PTSD

C., a Vietnam War veteran, had been expecting me. He was waiting outside his house with a motorbike lock to hand — anticipating that I may arrive to interview him on a two-wheeled vehicle having forgotten my own lock. This forethought was unnecessary: I took a taxi. We exchanged small talk as I set up my voice recorder, preparing to begin our conversation and delve into his past.
‘You know,’ C. suddenly said, ‘I stopped going to the fireworks after the war. It’s with any loud noise — I automatically throw myself down onto the ground. It’s dreadful!’ After a short pause, he continued, ‘I rarely sleep well. Nightmares. Bad flashbacks. I sometimes freeze just thinking about it’.
It occurred to me then that everything C. had just described: involuntary flashbacks, nightmares, irrational reactions to certain triggers… are all suspiciously similar to the ICD-10-outlined symptoms of post-traumatic stress disorder (PTSD), which cab be experienced by as many as 30% of war veterans. It isn’t difficult to surmise that C. has been living with these symptoms for 40 years. To put this into context, 3 months of experiencing such symptoms is considered to be in line with a diagnosis of chronic PTSD.
This brief episode reaffirmed just how little public awareness there is about PTSD, and how what is known is highly stigmatized. Even whilst in the army, patients face misunderstanding and disapproval as outbreaks of fear are seen as manifestations of weakness. Arriving home isn’t much better; family and friends often have no idea how best to approach what can be dramatic changes in the character of someone they love. Let’s talk about it, then.
PTSD is characterised as a normal reaction to abnormal situations. Fundamentally, this disorder indicates a failure of the neurobiological systems responsible for stress and vigilance to adapt to trauma. Both are very important skills from a survival point of view. Thousands of years ago, these systems saved our ancestors’ lives during perilous situations (say, facing a predator) by sharply raising their level of stress and initiating the internal command: “Flee!” Or “Fight back!” It is of course, from our understanding of this neurobiological reaction that we coined the well-known phrase ‘fight or flight”. As it was designed for survival purposes, this response is automatic. However, if parts of the brain are strained for an extended period of time (as is often the case during combat), something is likely to be disrupted and go wrong.
In particular, fMRI scans show that the amygdala — the part of the brain that plays an active role in regulating fear (and emotions more generally) — has a tendency to be hyperactive in patients with PTSD. It is almost as if the brain “encodes” the negative experience more than is actually necessary. As a result, it is no longer able to regulate irrational outbursts of fear and hypervigilance experienced by the patient. Moreover, this also explains why flashbacks sometimes occur with no apparent cause or after interactions with a tenuously-related trigger: a hyperactive amygdala is signaling the presence of danger and simultaneously evoking a traumatic memory to remind a person why this trigger is dangerous. This is a normal method of self-defense, but one which, in cases of PTSD, is accompanied by debilitating side effects.
On the contrary, another part of the brain — the hippocampus, responsible for recognizing new and old memories — decreases. This negative impact upon the hippocampus’ functionality can have noticeable affects in day to day life, as it translates into a diminished ability to distinguish between the old and the new. For most readers it will be self-evident that memories relate to the past, in the form of, for example, stories or associations. This is due to the work of interrelated neurological systems that firmly integrate memories into the system of emotions. However, in those living with PTSD, the separation between “past” and “present” becomes clouded, because the mechanisms responsible for the process of “coding memories” are damaged. Understanding these neurological changes can help us rationalise why traumatic memories seem worse than they are — after all, for patients suffering with PTSD, they are not memories. The past does not belong to the past, but remains practically unchanged and domiciled in the present. The following quote summarises this issue of neurologically interwoven time spans very well: “PTSD occurs not because a person refuses to let go of the past, but because the past refuses to let go of the person.”

PTSD is not only influenced by changes in parts of the brain, but also by neurotransmitters — substances which help brain cells (neurons) transmit information to each other. In cases of PTSD, there is an abnormal regulation of catecholamine, serotonin, and other substances that play a major role in stress and fear (both real and perceived).
Could it be that some people are more predisposed to PTSD than others? Biologically, yes. For example, one study measured the size of the hippocampus in monozygotic twins, where only one of the two was a veteran. Some veterans had PTSD, some did not. I should mention here, that studies on twins are particularly valued in medicine, biology and psychology, since they make it possible to separate “nature” from “nurture”. If one of the two genetically identical people has a deviation from the norm, scientists generally interpret it as the result of their environment. As expected, veterans with PTSD had a smaller hippocampus than in psychologically healthy veterans. What is interesting, however, is that even in their twins — who did not serve — the hippocampus was of an abnormal size.
But there is light at the end of the tunnel. Biological predisposition to PTSD does not necessarily cause symptoms — environment, social support and other factors can increase or reduce the risk of the disorder. They can also contribute to effective treatment — and the symptoms of PTSD can be improved (up to 70% of patients show signs of improvement after treatment). Veterans can turn to drugs, cognitive therapy … and there is even a special type of therapy based on the processing of eye movement (EMDR). During EMDR therapy, the patient recounts the traumatic moment whilst simultaneously following other stimuli (moving their eyes in accordance with their therapists’ instructions, slapping their arms, etc). The theory behind this particular therapy suggests that a shift in attention from a traumatic event onto alternative stimuli helps the patient to rework and recode information until it ceases to be traumatic. There appears to be some truth in this concept as research suggests that such therapy is as effective as medication.
And finally — just in case you are wondering how my interview with C. ended — after our conversation, I told him a little about PTSD and left him with a list of psychological centers specializing in the disorder (standard research procedure). I had previously called these centers and asked them to provide assistance to my participants for free. And whether or not treatment would be beneficial in this particular circumstance, is in the end, a question that can only be answered by C.
*Parasites of the mind: name given to traumatic memories by French psychiatrist Jean Martin Charcot
